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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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YAKUTAT BAY GLACIERS                                     SB
butes little ice to the plateau; but just to the west of theHayden the great Marvine Glacier descends from the mountains and supplies the ice which forms the easternmost of the four lobes of the Malaspina Glacier. The low ice cliff of this lobe of the glacier lies just back of the west coast of Yakutat Bay from near Point Manby to the Kwik River, being separated from the sea by a fringe of alluvial fans across which many large, swift, glacial streams flow. The Marvine lobe of the Malaspina Glacier is of distinct present interest because of the rapid change from stagnation to activity which was observed in 1906.
East of the Malaspina Glacier, and between it and Yakutat Bay, are three glaciers which extend beyond their mountain valleys and spread out in piedmont bulbs. The largest of these, the Lucia, is the westernmost and it is now separated from Malaspina Glacier, to which it was undoubtedly formerly a tributary, only by the gravels of the Kwik River alluvial fan. Immediately east of the Lucia, and coalescing with it, is the piedmont bulb of Atrevida Glacier. Both of these bulb glaciers are partly covered with ablation moraine and on their outer stagnant termini support forests of alder, cotton-wood and spruce. Atrevida Glacier changed from a stagnant to an active condition between September, 1905, and June, 1906, and Lucia Glacier was changing in 1909. Galiano Glacier, the smallest of these three glaciers, changed from stagnation to activity sometime between 1890 and 1905, probably after 1899. Its piedmont bulb extends practically to the shores of Yakutat Bay from which it is separated only by a narrow gravel beach. Two or three miles to the east of Galiano Glacier is the still smaller Black Glacier, which has no piedmont bulb, and is interesting especially because, though so near the Galiano, it gives no evidence of having undergone notable change in condition.
On the west side of Disenchantment Bay is the large Turner Glacier, a tidal glacier with an ice cliff 2^ miles in length, which, though changed slightly each time it has been observed, shows no such pronounced variation in condition as those just mentioned. Just north of it, however, is a smaller glacier, called Haenke Glacier, which, like the Atrevida. was absolutely transformed between 1905 and 1906, having become broken and having advanced nearly a mile and assumed tidal condition in an interval of ten months. Just north of this is the small Miller Glacier, which had a similar transformation about 1901.
Next to these is the Hubbard Glacier, the largest tidal glacier in the region, fed by two large tributaries from some unknown source far back among the mountains and having a tidal front 5^ to 6 miles in length. It presents many interesting features, and in 1909 had a very slight advance. Variegated Glacier, whose piedmont ice bulb coalesces with the southeastern side of the Hubbard, presents the interesting condition of a piedmont bulb in a valley, instead of at the base of the mountain front. It resembles Atrevida and Lucia Glaciers in its ablation moraine, though it lacks forest growth. It rivals Atrevida Glacier in the extent of its transformation between 1905 and 1906. Almost coalescing with the Variegated is the Orange Glacier, entirely confined to its mountain valley, unchanged since first observed by us in 1905, and forming the western end of a through glacier, whose other end is just back from the shores of Nunatak Fiord. Near the southeastern end of this through glacier, a hitherto unnamed glacier, to which we have given the name Butler Glacier,1 descends from the mountains, and
ğAfter Mr. B. S. Butler of the TJ. S. Geol. Survey, whose efficient aid contributed greatly to the success of the 1905 and 1006 expeditions to Yakutat Bay. 3